By ELIZABETH WEIL

November 8, 2013

The ever-earlier onset of puberty is reshaping the legendary Leipzig boys choir.

By ELIZABETH WEIL

Photographs by Rineke Dijkstra for The New York Times

November 8, 2013

After school and lunch but before afternoon rehearsals, the sopranos and altos of the St. Thomas Boys Choir in Leipzig, Germany, tried to master their skateboards, while the tenors and basses kissed their girlfriends and texted. Thoralf Schulze, the Latin teacher and the choir’s dean, walked among them, describing each with the analytical intimacy of a coach, calling out the age at which each chorister’s voice broke and how long he sat benched before he could sing with the choir again.

“Twelve! Six months only!”

“Twelve! One year!”

“Thirteen! One year!”

“Thirteen! Six months!”

The boys live at St. Thomas and attend a public school nearby. Schulze entered the boys’ dorm, called the “alumnat,” and walked up the stairs, extending a hand to a handsome young bass. “Adrian,” Schulze said smiling with relief. “He was 15.”

Puberty is always momentous, awkward and bittersweet, but perhaps nowhere more so than here. The St. Thomas Boys Choir is 801 years old. Johann Sebastian Bach served as its Thomaskantor, or choirmaster, from 1723 to 1750, during which time he complained about the boys’ lack of musical talent and paid a co-worker to take over the Latin class that he was also supposed to teach. Since then the choir has become something of a Bach historical re-enactment program — a homage to its greatest musical director; not quite Colonial Williamsburg but inching in that direction.

Each weekday, the choir rehearses under the direction of Georg Christoph Biller, a stern man with wild hair. Each Friday, when they are not traveling in Germany or abroad, they sing a motet at St. Thomas Church. Then, during the weekend, as it has for at least 200 years, the choir usually performs a composition by Bach. (The choir will be singing at Lincoln Center on Nov. 12.)

But maintaining Bach’s legacy has become more difficult. The problem is with the sopranos. At St. Thomas, as in all boys choirs, the oldest of those singers with unbroken voices are the most prized. Like flowers that are most beautiful just before they die, these boys have the most power, stamina and technique. There are scholars who say that in Bach’s day, some boys’ voices didn’t change until as late as 17. Now boys’ voices are changing earlier, a lot earlier. Medical records tracking puberty through history do not exist, but Joshua Goldstein, chairman of the demography department at the University of California, Berkeley, has analyzed mortality patterns among boys, which can show increased risk-taking and, by extension, the onset of puberty. His research suggests that the age of puberty for boys has dropped, on average, 2.5 months a decade since the mid-1700s. That would mean that boys are sopranos for a shorter time. To maintain a well-stocked soprano section, St. Thomas needs to start with and train more boys. To house growing numbers of recruits, the choir has built a new, larger glass-and-steel-frame alumnat.

Schulze poked his head into some of the boys’ living quarters, a warren of twin beds, messy desks and pictures of rock bands and beautiful women taped to the wall. For centuries, choristers of all ages have lived together in suites, the older taking care of the younger in St. Thomas’s prefect system. But the gap between the “knowing and unknowing” or “bearded and unbearded” boys, as various music scholars have put it, is becoming wider. Boys enter the choir at the start of fourth grade, age 9. Some in the alumnat still miss their mothers; a few call home at night and ask to sleep there. But nine years later, when the Thomaners graduate from high school and the choir, many no longer fit the angelic chorister model. One corner of the suite could have been in a frat house: free weights, beer bottles, deodorant, soccer balls.

Schulze didn’t seem concerned about the collegiate-style mess. One of his goals is fostering what he calls normal boys who know how to relax and enjoy themselves outside rehearsal. What he cares about, as does everyone at St. Thomas, is the singing. Leaving the suite, on the way to his office, Schulze passed the laundry room, its clothes racks filled with the Thomaners’ performance outfits: blue jackets and pants for the older boys, the tenors and basses; sailor uniforms for the sopranos and altos. The younger Thomaners’ costumes were better than robes and ruffles, the fate of boys in other choirs. But who wants to wear a big infantilizing sailor collar into his teens? I asked Schulze at what age, in his estimation, voice change would ideally occur — when he would like to see the boys switch from sailor suit to jacket and pants. “Fifteen would be not so nice for the boy,” he said, “but for the choir, sublime. He comes to live at the alumnat at 9 years. He’s at the level of the choir at 10. If he goes at 12 for voice break, we have only two years together to get the music made.”

Weeks generally have a rhythm at St. Thomas. Learn new music on Monday. Perform throughout the weekend. Race like crazy to prepare in between. On the Tuesday I visited last spring, the boys woke up at 6:45 a.m., as always, ate breakfast at 7:10 a.m., attended school from 7:30 a.m. to 1 p.m. and then ate lunch. Some of them later went back to school while others had free time until their afternoon lessons and rehearsals. Next was practice with the whole choir at 6 p.m., then dinner at 6:45 p.m.

In a brick building near the alumnat called the Villa, Biller sat behind a grand piano dressed in a black turtleneck and black pants. Biller, who is 58, is the 16th Thomaskantor since Bach. Bach was almost not a Thomaskantor at all; he was offered the job only after two other men turned it down.

About 10 minutes into the soprano rehearsal, a young singer in a Ron Jon T-shirt opened the heavy door and took his place among the 10 other sopranos. Biller raised a formidable eyebrow.

“Why have you not joined us earlier?” Biller asked in German. (A bass with a British mother translated for me.)

“I was playing soccer,” the boy said.

Ashamed but not ashamed enough, the soprano took a seat under an ancient chandelier. Behind him sat a boy a head taller than he, a Harry Potter look-alike named Lukas — thin, with round glasses, excellent posture and sweeping hair. Biller nodded at Lukas. Earlier he had praised the older boy saying, “You are almost ready to lead the section now.” But how long could Lukas maintain that role? Puberty is typically a three-year or four-year process, with a growth spurt that starts before voice change. Already Lukas’s pants looked a little too short.

Biller, conducting with facial expressions while his hands were tied up playing piano, led the sopranos through “O Domine Jesu Christe,” a motet written by Johann Hermann Schein, who was a Thomaskantor a century before Bach. The boys sounded a little weak and fuzzy but still beautiful, precisely the sound that people have loved for at least 500 years. Of course, achieving that sound has been tricky for as long as it has been treasured. Griping in 1547, the Swiss music theorist Heinrich Glarean wrote, “Boys especially could sing the highest voice if they were not frequently unacquainted with the song.” In 1668, Bénigne de Bacilly, a French vocal instructor and composer, voiced what has been a persistent complaint: “As soon as a teacher has taken great care and pains to train a boy’s voice, it disappears.” At one point, Bach presided over 55 choristers, about a quarter of whom were sopranos, and he listed 17 of them as “unproficient.” (There are 106 today, including only 11 sopranos.) But the challenges were part of the job, and Biller had no time to waste. It was his second of only five rehearsals with this section that week. In three days, well-prepared or not, they would sing in St. Thomas Church on risers in front of Bach’s grave.

Toward the end of the session, Biller turned to Bach’s “Mass in B Minor” and began to offer a lesson. Along with teaching music, Biller was charged with maintaining a cultural legacy. “What is Bach’s idea?” Biller asked the boys as they opened their worn scores.

Nobody answered. Biller’s brows pinched. He soon excused the sopranos, and the tenors and basses entered, their bodies filling the room. Their diction sounded crisp, their voices strong. Finally, singers old enough to handle the music. Biller’s face relaxed.

“Now we have the possibility of a young boy sounding like Joe Cocker,” Michael Fuchs, an ear, nose and throat specialist and the voice doctor of the choir, told me. “We can have an early adult voice without an adult personality. He sounds like his father when he’s still a boy.”

Fuchs’s own voice broke in 1983, when he was a Thomaner, age 13. He liked the voice doctor of the choir then and decided to follow his career path. Now trim, goateed, in good shoes and fashionable eyeglasses, he’s among the world’s experts on the timing of voice break. Certainly nobody cares more. “We have a problem in the choir,” Fuchs said, when we met in his office at Leipzig University hospital, echoing concerns I heard time and again. “The balance is shifting. We have more men’s voices and fewer boys’ voices.” The obvious solution — starting boys in the choir at 8 instead of 9 — does not work. The choir tried, and the 8-year-olds couldn’t handle life in the alumnat, learning all the pieces and attending all the rehearsals. So the plan now is to squeeze every day out of the soprano voices. “We try to let the boys sing as long as possible without risking overloading the boys and damaging the voice,” Fuchs said. Many of the Thomaners hold Fuchs in mystical esteem, claiming he can predict to the day when their voices will break.

In the years before the boys hit puberty, Fuchs saw them every three months to record growth, hormone levels and voice. He played for me recordings of one boy speaking and singing the same passage of a choral piece every year from age 11 to 14. Even to my untrained ear, the differences over time sounded stark, the boy’s voice becoming richer and fuller until the day it shattered. Mining data from the recordings, Fuchs constructs scatter plots showing changes over time in jitter (variation in pitch), shimmer (variation in loudness), noise component (breathiness) and range. All this data provides context so that he can distinguish what is causing flaws in a boy’s voice. “Is it a cold? A problem of singing technique? Voice break can sound like laryngitis.”

Martin Ashley, founder of Boys Keep Singing, a British group dedicated to keeping boys in choirs, is the author of the monograph “How High Should Boys Sing?” In it, he quotes a vocal expert who describes the boy-chorister sound as “clear, cold, piercing and transparent . . . disembodied, ethereal and ghostly . . . enchanted, naïve and guileless.” A typical boy’s voice falls from about 500 Hz as a baby to 300 Hz as a toddler to 200 Hz before puberty, and it’s the last sound that choir directors and listeners crave. In 1927, “Hear My Prayer,” by the 15-year-old British soprano Ernest Lough, became HMV’s first classical record to sell a million copies. In 1955, Keith Richards, then 11, performed in Westminster Abbey with two other boy sopranos for the queen.

To see how a boy is maturing physically, Fuchs threads a tiny camera through the nose and into the larynx so he can watch and record the vocal anatomy while the boy sings. (When Fuchs was a Thomaner, the doctor used what amounted to a dental mirror on a long, narrow stick to see into their throats; by comparison, Fuchs said, his test wasn’t bad, once the boys learned to control their gag reflex.) The videos are intimate and alarming — the vibrating glottis, the gaping trachea: Jonah’s view from inside the whale. “That red is the leading edge of cells growing,” Fuchs said, pointing to a vocal fold on his computer screen. “Can you hear how it’s not possible to bring the vocal cords into good vibration?” he added during a particularly scratchy patch. “If this were from overstress and not voice break, you would see it on the surface. Like if you went to the forest to cut wood. You’d have nodules on your hands and edema. Stress on the vocal cords looks the same.”

While their voices are changing, Thomaners don’t rehearse or perform, but they still have bi-weekly singing lessons, during which they work on diction and breath control. Singing too much while your voice is changing can lead to bad habits and injuries, similar to an athlete playing hurt. Late Wednesday afternoon, a tall, awkward, 13-year-old named Alexander spent half an hour with a private instructor, meticulously enunciating — la-pla-lu ma-la-plu, la-pla-lo ma-la-plo — and making sounds like deflating balloons and air compressing into tires. His teacher was a lovely young concert singer in an argyle sweater and white boots. She massaged the stress out of Alexander’s jaw and neck while he did his best to stare at the wall. “Va vey vop voop veep vip.” Toward the end of the session, Alexander sang scales ranging two octaves, his teacher writing down which notes he lost at the top, dropped in the middle and gained at the bottom.

This was nobody’s fantasy of being a Thomaner, but you can’t stop the body from maturing — even though the thought has occurred at St. Thomas. “Of course, Cantor Biller asks me at times, ‘Do you have some idea to delay onset?’ ” Fuchs said. Puberty-stalling drugs do exist. They are prescribed by endocrinologists for children with extremely early sexual development. But preserving sopranos’ voices through chemistry? Not even the most passionate choir fans suggest using pharmacology to replace the bygone castrati. “That’s absolutely forbidden from the medical point of view,” Fuchs said.

Thursday evening, Georg Biller sat on a stool in front of the entire choir in the atrium of the public school, which was being used for rehearsals until the new alumnat was completed. A 12-year-old, on voice break, stood by his side and turned pages of music for him. Biller directed the choir with his hands and used his head, too, as a conducting tool, forehead and eyebrows working together in a facial interpretive dance. The next day at 6 p.m., a few hundred people would file into St. Thomas Church to hear the choir perform. Leipzig has a half-million people. BMW and Porsche have plants on the outskirts, but the city’s heart and identity remain in music. Bach, Wagner, Schumann and Mahler all lived and worked in Leipzig. In 1936, the mayor refused to follow Nazi orders to destroy a Mendelssohn statue. (It was destroyed anyway.)

Biller took “O Domine” from the top. After a minute he folded his hands and stopped the singing. The sopranos were flat.

Many at St. Thomas hope the sopranos will have an easier time if they receive more early training. In 2008, an organization affiliated with the choir opened a kindergarten, where children learn to read and write music at the same time they learn to read and write words. Each morning I was there, 5-year-olds with slippers on the wrong feet sang “Hänschen Klein” and played rhythm games, listening for light or ominous sounds as their teacher played piano. On the wall outside the kindergarten’s administrative office hung violin-shaped hooks and paint-by-number portraits of Bach. “We are able to realize very soon if a boy will be able to be a Thomaner,” Heike Hübler, the kindergarten administrator at the time, told me. “Maybe 60 to 70 percent learn an instrument, too, piano or violin, outside of school.”

In addition, Lana Toschev, the primary scout for the choir, scours Leipzig’s other kindergartens, searching for boys who can sing at least an octave above middle C. Those boys can join St. Thomas’s music program in partnership with a public elementary school, where she trains the boys four days a week. That Thursday she sat at a baby grand piano before a semicircle of 7-year-olds, including her own son. Few of their feet reached the floor. Most of their just-in adult front teeth looked too big.

One by one, the boys walked over to the piano bench. Toschev plinked a note; the boy, as directed, sang that pitch and then a third above.

“Every day is hard work,” she told me. Still, they all wanted to be Thomaners. Not as much as they wanted to be professional soccer players or cyclists or pilots, but being a chorister ranked high among their dreams. Toschev’s pupils are not guaranteed a spot in the choir; they compete in auditions with boys throughout Germany. “Maybe 70 percent will be able to be Thomaners,” Toschev said as she erased notes from the music staff on the chalkboard. “They are very valuable, these boys. Without them, the Thomaner choir cannot exist. But they have to be intelligent, they have to love music, they have to have rhythmic feeling.”

Back in the atrium, Biller began the next pass through the motet. This time, the sopranos overcorrected; they sounded sharp and screechy. The third time, Biller asked them to stand and sing. Generally, he works the sopranos longer and harder than any other section. While the young boys sang, a few older boys furtively pulled out smartphones, but most sat poised and paid attention. At last, on the fourth pass, the sound was better, the high notes clear and bright.

After rehearsal, on the way to dinner, I asked one of the tenors how he felt when his voice changed. “Of course, you want to be a man,” he replied. “But you are only a boy once, and here, when your voice breaks, you are a bit . . . angry.”

Bach scholars and musicians question whether trying to wring passable Bach out of tweens is worth the trouble. Why not just have older females sing the soprano roles? Who would know the difference?

There have been studies that try to answer this question; they are sort of like studies that try to detect whether people can distinguish between cheap and expensive wine. Judging blind, few can tell the two apart. Bach used boy sopranos at St. Thomas because it was an all-male institution. But he is also known to have on occasion employed female sopranos, boy sopranos and adult males singing falsetto. “I fear I can’t see any evidence that Bach cared particularly about boys at all,” Joshua Rifkin, a conductor and professor of music at Boston University, told me. “All of this is our modern projection back.”

In addition, Rifkin said, given his youth and inexperience, “the boy singing today is further away from the boy of Bach’s day than the woman singing now is from the woman of Bach’s day.” Records of Bach’s 1729 audition show a number of 13- and 14-year-olds entering choir. Joseph Haydn still had such a good soprano voice well into his teens that his choirmaster encouraged him to have surgery to make him a castrato. (Haydn’s father objected, however, and he was spared.) “It’s a terrible parallel to draw, but we don’t have that instrument,” Rifkin continued. “Just like we don’t have castrati.”

But in fact, in many ways, the choir is more invested in its all-male tradition than ever. Before the Berlin Wall fell, Leipzig and St. Thomas belonged to East Germany, and the state ran the choir. “In the former time,” Stefan Altner, the general manager of the choir, told me, “it was all the central agency from Berlin: ‘You have to make a tour in Japan. We organize it for you!’ ” Now, he said, “We are responsible for bringing the choir to the worldwide market.” The modest admission price for the Thomaners’ Leipzig recitals and the small fee the parents pay do not cover the choir’s costs. The city of Leipzig, along with the Thomanerchor foundation and a parents’ association, provide significant financing. Yet the pressure to raise money remains. “We make films, we do radio, we talk to journalists and to media for the choir’s future,” Altner said. “Always when you go on stage, you have to be so good that each person in the audience can compare the sound with the CD and compare it with other choirs on the market. Always you have to be so good as to be the best.”

Friday afternoon the Thomaners, in their skinny jeans and sneakers, stood on the balcony of St. Thomas Church and rehearsed the motet one final time. Tourists below paused and snapped pictures as Biller worked the sopranos again and again. Some of the music sounded so sad, so burdened, so aware of death, it was hard to imagine how the boys could connect with it. Two very old men shuffled in and sat on the wooden pews. Just across the brick plaza stood the Bach Archive, which includes a repository for 18th-century instruments still used for occasional performances. In a strictly rational sense, the boy sopranos might belong there as well. But as Andrew Parrott, the British conductor famed among aficionados for his historically informed performances of Bach, said: “We may have gotten emotionally attached to the presence of the boy in a nonmusical way.” Rifkin added: “There’s something utterly magical and profoundly heart-wrenching about it. Maybe particularly in music, where people have to reach into and give you something so deep from within themselves.”

After the final rehearsal, the boys walked back through town. At 4:15 p.m., a bell rang in the alumnat signaling that it was time for the sopranos and altos to line up in front of Simon Jacobs, an 18-year-old bass. Jacobs was the Thomaners’ domesticus, and every Friday evening he sat on an ornate wooden chair and inspected the young boys to make sure they looked concert ready — shoes shiny, sailor jackets straight, hands clean. In his cluttered suite, fabric brush in one hand, shoe polish in the other, Jacobs spun around a 10-year-old, smoothing the back of his jacket and picking some loose threads. According to Thomaner tradition, tenors and basses are spared this ritual. The choir assumes a singer with a broken voice can dress himself. Lukas, among the choir’s most talented sopranos, dashed into his room five minutes late, changed quickly into his sailor suit and headed back out again without stopping for inspection. Just before the concert, I asked him why he skipped the domesticus ritual. “Today is my birthday!” Lukas said. “I turned 13.” Presumably, he felt too old.

The church bells rang at 6 p.m., and the Thomaners walked two by two from the back of the church to the front. Passing through the crowd, the boys seemed marvelous and otherworldly. So much about the concert was humble: the risers, Biller’s conductor’s stand, the audience in sensible shoes and jeans. But the singing was magnificent, soaring and poignant and hard won. When the choir finished, Biller bowed very slightly, and the boys walked back through the sanctuary again, spilling out onto the church stairs and into the night. The older Thomaners clutched their girlfriends, the younger ones, their mothers. Fuchs suspected that Lukas’s soprano would last no more than a year longer, two at most. Then his ethereal voice would slip away, joining all those that rose and fell before his in St. Thomas Church.